Loss of genetic variability in natural populations affects negatively the adaptive and evolutive process of plant species. In this context, the objective of this work was to evaluate the existing genetic variability between and within natural populations of P. platycephala, using biometric characters of fruits and seeds and physiological characters of seeds and seedlings, and, thus, assess the potential for selection of mother trees, indicate areas for seed collection and use, and generate support for conservation and pre-breeding of plant species. A completely randomized experimental design was used, with 45 treatments (progenies) and four replications of 25 seeds. The progenies were evaluated in laboratory, using seeds collected from 45 mother trees sampled in three natural populations. The following characters were evaluated: seed germination percentage, germination speed index, and mean germination time; shoot and main root lengths; and seedling shoot and root dry weights. The data were subjected to RELM/BLUP analysis for estimating genetic parameters and correlations and to analyses of genetic divergence (UPGMA). The populations present genetic differences to each other and a significant variation between progenies for all characters evaluated, and the variation was greater within the populations. The characters evaluated present high genetic control; therefore, they can be used in analysis of genetic variability of populations and progenies of P. platycephala, thus assisting in the identification of areas for seed collection, conservation programs, and pre-breeding of the species.

Genetic variability among morphometric traits of fruits and seeds of native species is crucial for divergence studies within and between populations, supporting genetic improvement programs and strategies for seed collection. This study aimed to evaluate genetic divergence within and between populations of P. platycephala based on morphometric traits of fruits and seeds. Ten progenies from two populations (Eugenópolis and Bom Jesus, approximately 20 km apart), located in Bom Jesus, Brazil, were analyzed. A random sample of 100 fruits from each progeny was selected, seeds were extracted, and the number of seeds per fruit was counted. A sample of 100 seeds from each progeny was measured using a digital caliper and tape measure. Data analysis was performed using mixed models in a completely randomized design with 10 unrelated genotypes and 100 plants per plot. The genetic divergence analysis revealed similarity between populations (Fixation index between populations Fst ranged from 0.01 to 0.28) and dissimilarity among progenies, with the number of seeds per fruit being the most significant trait for forming distinct progeny groups. Heritability values above 0.32 for traits like seed size and width indicate that over 30% of the variability in fruit and seed morphology is of genetic origin. Progeny 1 from group 3 stood out, showing more divergent traits, such as greater fruit and seed thickness and a higher number of seeds per fruit. Future studies should select progenies from different genetic groups for crosses to enhance genetic variability and improve fruit and seed production.